1. Field
The present invention relates generally to wireless communication networks and packet switched data networks, and more specifically, to supporting authentication of wireless communication devices accessing the services of packet switched data networks.
2. Background
The field of wireless communications has many applications including, e.g., cordless telephones, paging, wireless local loops, personal digital assistants (PDAs), Internet telephony, and satellite communication systems. A particularly important application is cellular telephone systems for remote subscribers. As used herein, the term “cellular” system encompasses systems using either cellular or personal communications services (PCS) frequencies. Various over-the-air interfaces have been developed for such cellular telephone systems including, e.g., frequency division multiple access (FDMA), time division multiple access (TDMA), and code division multiple access (CDMA). In connection therewith, various domestic and international standards have been established including, e.g., Advanced Mobile Phone Service (AMPS), Global System for Mobile (GSM), and Interim Standard 95 (IS-95). IS-95 and its derivatives, IS-95A, IS-95B, ANSI J-STD-008 (often referred to collectively herein as IS-95), and proposed high-data-rate systems are promulgated by the Telecommunication Industry Association (TIA) and other well-known standards bodies.
Cellular telephone systems, configured in accordance with the use of the IS-95 standard employ CDMA signal processing techniques to provide highly efficient and robust cellular telephone service. Exemplary cellular telephone systems configured substantially in accordance with the use of the IS-95 standard are described in U.S. Pat. Nos. 5,103,459 and 4,901,307, which are assigned to the assignee of the present invention and incorporated by reference herein. An exemplary system utilizing CDMA techniques is the cdma2000 ITU-R Radio Transmission Technology (RTT) Candidate Submission (referred to herein as cdma2000), issued by the TIA. The standard for cdma2000 is given in the draft versions of IS-2000 (cdma2000 1×EV-DV) and IS-856, (cdma2000 1×EV-DO) and has been approved by the TIA. Another CDMA standard is the W-CDMA standard, as embodied in 3rd Generation Partnership Project “3GPP”, Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214. The W-CDMA standard is in the process of incorporation into a GSM-based system known as Universal Mobile Telecommunications Systems (UMTS).
The telecommunication standards cited above are examples of only some of the various communications systems that can be implemented. One general category of standards is referred to as “Third Generation” or “3G,” of which cdma2000 and W-CDMA are both members. These 3G standards are directed towards increased data rates, which will support increased user numbers and data-intensive applications.
Given the growing, demand for wireless data applications, the need for very efficient wireless data communication systems has become increasingly significant. One such wireless data application is the transmission of data packets that originate or terminate at packet switched data networks. Various protocols exist for transmitting packetized traffic over packet switched data networks so that information arrives at its intended destination. One such protocol is “The Internet Protocol,” RFC 791 (September, 1981). The internet protocol (IP) breaks up messages into packets, routes the packets from a sender to a destination, and reassembles the packets into the original messages at the destination. The IP protocol requires that each data packet begins with an IP header containing source and destination address fields that uniquely identifies-host and destination computers.
The transmission of data packets from the IP network over a wireless communication network or from the wireless communication network over the IP network can be accomplished by adherence to a set of protocols, referred to as a protocol stack. Typically, a wireless communication device communicates with a base station (BS) and/or packet data serving node (PDSN) through an interface. A wireless communication device may be the origination or the destination of the IP packet, or alternatively, the wireless communication device may be a transparent link to an electronic device. In either case, payload information is broken into packets wherein header information is added to each packet. The IP header sits on top of the PPP layer, which sits on the RLP layer, which sits on top of the physical layer. The RLP layer is the Radio Link Protocol layer, which is responsible for retransmitting packets when a transmission error occurs. The PPP layer is the Point-to-Point protocol layer, which is an encapsulation, protocol for transporting IP traffic over point-to-point links. The packets are transported over the air to a BS/PDSN, whereupon the packet is subsequently sent over the IP network.
There are numerous difficulties that abound when attempting to wirelessly transfer data that originates or terminates in wired environments. One such difficulty is the authentication of the wireless terminals that attempts to access such packet data services.